Window ventilator



March 23, 1937. E. F. CHITTENDEN WINDOW VENTILATOR 2 Sheets-Sheet 1 Original Filed Feb. 12, 1934 E. F. CHITTENDEN V March '23, 1937.

wxuno w' VENTILATOR Original Filed Feb. 12, 1934 2 Sheets-Sheet 2 mmw Rea med Mar. 23, 1937 I UNITED v STATES PATENT OFFICE No. 710,877, February 12, 1934. Applicatlonfor reissue September 14, 1936, Serial No. 100,702

'10 Claims.

This invention relates to ventilators, but more particularly to apower driven ventilator adapted to be disposed between the sill and lower sash of a window for forcing air into a room and diffusing the same therein.

An object of the invention is to provide a packed steel wool, glass wool, or other mineral wool, in such a way as to filter out pollen and like material, aswell as the coarser'dust, and

force thefiltere'd air into the room upwardly so thatit moves to the ceiling of the room being ventilated, and there spreads out before settling, so that drafts are avoided.

, Details and further objects of the invention will appear as the description proceeds.

For purposes of illustration, but not of limitation, apparatus in accordance with one embodiment of the invention is shown on the accompanying drawings, in which:

Figure 1 is a perspective view of ventilator installed between the sill and window sash;

Figure 2 is a front elevation of the ventilator with the front wall or panel removed; and Figure '3 is an end elevation of the ventilator with a side wall' removed. The illustrated apparatus comprises a window ventilator which is adapted to be installed between the sill I0 of a window opening and the lower window sash ll thereof, it being merely necessary to raise the sash, insert the ventilator, properly secure the ventilator in place, and lower the sash against the upper portion of the ventilator, as will hereinafter appear, The ventilator comprises a housing having a front wall or panel l2, side walls l3, and a bottom wall l4. The

Flgure 1. The forward portion of the bottom wall l4 extends downwardly, as indicated at I4,- whilethe rear portion inclines downward at [5,

and then inclines upwardly providing an inclined portion I6 which terminates in an upturned flange H. The rear of the housing is open to provide an inlet H, which is controlled by a shield l8 having side wings l9 to prevent rain from entering the ventilator. The shield I8 is co-extensive with the housing and the wings l9 are adapted to lap over the side walls l3. The upper edge of the 5 shield is connected by a hinge 20 to a transverse strip 2! secured to the upper end of the side walls. Rods 22 connected to each of the wings I9 extend forwardly therefrom through openings provided in the front panel I2, and have a series of notches 10 23 to enable the shield to be secured in adjusted position. This enables the shield to be adjusted from the inside of the room, and adjustment may be made in accordance with the weather conditions. If desired, the shield can be entirely closed 15 providing an effective seal for the outer end of the ventilator.

Closing the top of the housing is a cover 24 which is connected to the strip 2| by a hinge 25. The front edge portion of the cover 24 is disposed below the top. edge of the front panel 12 and inclines therefrom downwardly and rearwardly, as shown at 26, and thence inclines upwardly and rearwardly, as indicated at 21. The extreme upper wall portion 28 extends at an angle to the -25 portion 21 inclining upwardly and rearwardly to the hinge 25. Flanges 29 depend from the opposite edge portions of the cover 24 to overlap the side walls l3 respectively. The arrangement issuch that when the sash II is raised, the cover 24 may be swung upwardly to reveal the inside of the housing. It will be seen that the construction is such that a comparatively small area is taken up by the ventilator, which would otherwise be efiective in shutting of light to the in- 35 terior of the room, and the raised rear portion enables a filter unit of sizable proportions to be used, as will hereinafter appear. It should be noted that the lower edge of the sash l I is adapted to rest against a downwardly inclined strip 30 secured to the rear face of the panel l2, and this strip also provides an abutment against which the free edge of the cover 24 rests.

As ,abovementiohed, the rear portion of the bottom wall ll of the housing is cupped at l6, and the cupped portion is disposed at an angle to the plane of the bottom wall with a portion thereof disposed therebeneath. This portion is substantially Parallel to the wall 28 of the cover 24. Arranged with the lower edge disposed in the cup portion I6 and the upper portion adjacent the cover wall 28 and the sides terminating I adjacent the side walls of the housing, is a removable filter unit 36, preferably of spun glass wool because of its extremely high eihciency for fllter- 55 arrangement, very little resistance is afforded to the e of air into the ventilator, and, be-

cause of the large area of the inlet, a substantial volume of air may be readily drawn in through} the inlet opening II with comparatively little efiort. The upwardly inclined portion 21 'of the cover forms with the upper wall portion 28 a socket into which the upper-portion of the filter,

unit 86 extends for assisting in retaining the uni in the desiredinclined position.

I Directly in advance of the filter unit and arranged closely thereto are fans II and 31 conjointly driven by an electric motor 33. The fans are preferably of a squirrel cage type, in which the air is drawn in axially and discharged radially. The fans are likewise arranged close to the front panel l2, which isprovided with. a series of louvers ll which direct the air upwardly. Preferably, the discharge openings provided by the louvers II should be of considerably less area than the area of the inlet opening ILand, conveniently, the area of the inlet opening II may discharge openings. 1 A switch I! on the front panel I! enables convenient control of the .motor 33. Projecting from opposite sides of the panel I! are wings II to which other panels may be attached toaccomeach of the side walls It, and engages the sill l0.

By turning the screw 38 the housing may be raised or lowered to the desired position. Screws ll extending through the flanges l9 secure the housing to thesill to hold the assembly rigidly in place.

It is to be observed that a glass wool filter unit 38, as referred to herein, is presently being sold on the open market, and consists of a fibrous mass in which the fibers are either of blown or spun glass coated-with an oily substance. The filter is enclosed in a housing of inexpensive sheet material such as paste-board, so that after a unitisfull of dirt and has served its usefulness, it can be thrown away and replaced by a new one. This can be conveniently donesince the cost of them-ls nominal.

Authorities have recommended drawing air through mineral wool filters, and other packed filters of the impingement type; at a, velocity of at least 300 feet per minute, their theory being that such high velocities cause foreign particles to follow comparatively straight paths so that they impinge upon and cling to the filter membersinstead of following thetortuous paths of the air through the filter. I have discovered that a much lower velocity is much more efilcient in removing very fine particles. such as pollen, by a filter of glass wool, or equivalent material. At the lower velocity the-particles settle and remain upon the filter members, whereas the higher velocities tend to blow them off of such members as they may impinge upon.

For these reasons I prefer to draw the air 75 through the filter at a velocity not exc di g 100 spreads out against the ceiling.

'perature inore even.

1 To reach the ceiling from window in the-usual dwelling with surety under be at least ten times the combined areajof the feet per minute,'and preferably around 50 feet per minute.

low velocity rises for a time and then curves outward and downward in a path similar to that of a thrown ball, and creates a definite objectionable draft as it returns toward the floor, and leaves undisturbed the blanket of warm air beneath the ceiling.

It will be noted that louvers ll discharge the air in substantially parallel contiguous sheets.

This has an effect on the air stream something,

scends gently and evenly without setting up an objectionable draft.

It also mixes with the warm air next to the ceiling, gently agitates substantially the entire atmosphereof the room, and renders the temthe bottom of a varyin'ggtemperature conditions, the upward Jet should afvelocity of at least 600 feet per minute. To allow for occasionally high ceilings K and conditions, I prefer to provide a BBDGI'QLDUIDDSQIHI imparting an-initial velocity of about 750 feet per minute to the discharged air. Occasionally .high ceilings may require higher velocities, but such conditions are ex-- ceptional, and such higher velocities, usually unnecessary, increase the cost of the fan, the

' energy required, and the difflculties from noise,

etc

34 is approximately one-tenth that of the crosssection of the filter normal to the path of air travel; but the upward slantof the discharged air reduces the cross-sectional area normal to its direction of movement, so that the actual discharge velocity is' about 750 feet per minute with an intake velocity through the filter of about 50 feet per minute.

As the filter becomes somewhat clogged with material, the eifective air inlet area is reduced,- so that for long and effective use of a filter it should have sufllcient cross-sectional area to provide an initial inlet velocity materially lower than the highest permissible. A well made glass wool filter retains high filtering eificiency for upwards.

of a year constant use in normal atmosphere with an intake velocity of 50 or 60 feet per minute. With this low velocity of intake, such a filter accords a very substantially greater degree of relief to hay fever patients than does a like filter through which air is drawn at a velocity of 300 feet per minute, as is customarily advised with this type of filter.

In the appended claims, the expression "mineral wool type filter" refers to a filter having filtering characteristics like those of glass, steel, and other mineral wool packs suitably treated for filtering purposes, as is customary. while .poliensettling velocity" refers to a velocity at which the pollen particles may settle and remain upon the filter members, instead of relying upon the momentum of the pollen particle to carry it into contact with the filter member. as is customary in impingement type filters.

It is to be understood that numerous changes It then de-- As pointed out above, the total area of louvers.

in details of constructioni; arrangemed and operation may be effected without departing from the spirit of the invention as defined in the ap- This application constitutes a continuation in part of application Serial No. 875,368, filed June 12th,'1983.

whatlclaimasnewanddesiretosecureby' Letters Patent is: i0 1. 'In' ventilating a room, the method which consists in drawing air through an inlet opening,-passing the air through a filterat a velocity not exceeding 100 feet per minute, and

ing the filtered air at an upward angle into thev room at a'velocity of at least 600 feet per minute. 2, In ventilating a room, the method which oonsistsindrawingairthroughaninletopeniris. the air slowly through a filter withappreciable pressure and dischargin'gthe'filteredair atan upward-angleinto room at a relatively means of forced. draft and ietl'gh'aving a combined cross-sectional areal of the order of one-tenth of the section throulh the filtering area. c

3. Ventilating apparatus comprising a box having a bottom, front and sides and a cover, means on the bottom for mounting the box on a window sill with its front substantially fiush with the window sash and its rear portion disposed outside of the window sash, the-cover being dispo sed outside of the window sash and pivoted at its rear end, and a removable filter across the box beneath the cover.

35 '4. Ventilating apparatus comprising a box having a bottom, front and sides and a cover, means' oh the bottom for mounting the box on a window sill with its front substantially flush with tbs, window sash, the cover being pivoted at its rear and having its front edge normally beneath the windowsash,andafiltermounted acrossthebox beneath the cover and removable when the cover is lifted. v 1

6. Ventilating apparatus comprising a box having a bottom,v fr nt and sides and a cover, a filter across the rear of the box, means on the bottom for mounting the box on a window sill:

with its front substantially flush with the window sash and its rear portion disposedoutside the window sash, the cover'being' disposed outside of, the window sash and pivotally mounted at its rear, and means on the cover holding the filter in place when the cover is lowered. 8. Ventilating apparatus comprising abox H '55 having a bottom, front and sidesand a cover,

means on the bottom for mounting the box on a window sill with its front substantially fiush with the window sash, a pivotal mounting for the rear of the cover, the bottom having a socket front wall thereof.

across its rear adapted to receive the bottom of a filter, and a filter mounted in said socket and extending across therear of the box, the cover being provided with a socket fitting over the top of the filter when'the cover is lowered. 5 'l. Ventilating apparatus comprising a box having a bottom, front and sides and a cover, means on the bottom for mounting the box on a window sill with its front substantially flush with the'window'sash, a pivotal mounting for the rear 10 of the cover, the bottom having a socket across its rear adapted to-receive the'bottom of a filter,

and a filter mounted in said socket and extending across the rear of the box, the cover being provided with a socket fitting over the top of 16 the i'ilter when the cover is lowered, there being' discharge openinss in the front of the box and a fan in thebox in position to draw air into the box through the filter and discharge it throush'said openings in the front of the box. 2

8 Apparatusfor ventilating a room comprising a housing having a front, bottom and side walls, means on the bottom of said housing for mounting it in a window opening between the window sash and sill thereof with the front wall 25 7 thereof substantially fiush with the inner surface of the window sash. a cover providing a top wall of said housing, said cover being hinged at the back and having its front edge normally positioned beneath the window sash, a'filter in the rear portion of said housing and disposed in ver tically inclined position, said filter being of an area approximately as great as the cross-sectional area of the rear-portion of the housing, there being an inlet opening in the rear of -the housing and discharge openings in the front thereof, and a fan in advance of said filter for drawing air into, the housing through said filter and discharging it throush said openings in the 9. Ventilating apparatus comprising a box having'a bottom, front and sides and a cover, means on the bottom for mounting the box on a window sill with its front substantially flush with the window sash and its rear portion disposed outside of the window sash, the cover being disposed outside of the window sash and movably mounted at its rear end, and a removable filter across the box beneath the cover. s

lolventilating apparatus comprising a .box having a bottom, front andsides and a cover,

means onthe bottom for mounting the box on a window 'sill'with its front substantially flush with the window sash. the cover being movably mounted at its rear and having its front edge normally beneath the window sash, and a filter mounted across the box beneath the cover and removable when thecover is moved away from the filter.

EDW'IN F. CHI'ITENDEN. 

